Internal combustion engine



A115524, 1937. c. M. BLANCHARD 2,090,662

l INTERNAL COMBUSTION ENGINE 4 Filed March 18, 0335 ATTORNEY.

Patented Aug. 24, 1937l UNITED STATES PATENT OFFICE Application March 18,

Claims.

The present invention, in general, relates to internal combustion engines and particularly to those of the two-cycle type. While applicable to explosion types of gas or gasoline engines, the 5 invention is shown and described in connection with one of the fuel injection, compression ignition type to which it is more especially adapted.

An object of the invention is to provide an internal combustion engine in which the cylinders will be efficiently cleaned of exhaust gases and filled with fresh air even when thev engine is operating at high rotative speeds.

Another object of the invention is to provide a two-cycle internal combustion engine designed to develop relatively high mean effective pressures in the cylinders.

A further object of the invention is to provide an arrangement of cylinders, pistons, and connecting rods resulting in a very simple, effective and economical construction and one which is especially compact in form.

Still another object of the vide a fuel injection engine having a particular arrangement of cylinders, and a combustion chamber so designed and related to the cylinders as to produce a desirable amount of turbulence in the working charge atthe time the fuel injection takes place.

Other objects and advantages of the invention will become apparent from a reading of the following description taken in connection with the accompanying drawing.

Broadly, the invention consists in an arrangement wherein a pair or pairs of parallel cylinders are provided one on each side of a crankshaft, and slightly offset from each other both at right angles to and along the axistherecf. A combustion chamber substantially conforming in shape to the entering fuel sprayis positioned between the two cylinders of each pair, in axial offset relation and in open communication with each, rthus providing a combined combustion space and communicating air passage between the individual cylinders of each pair. By oi!- setting the cylinders along the axis of the crankshaft, a construction is made possible wherein a separate connecting rod for each piston of a pair may be connected to a common crank pin, thus conserving space and making possible the use of mdupnte parts and the elimination of others. By offsetting the cylinders from each other on each side of the crankshaft in a direction, at

right angles thereto, it is possible, due to a resultant varying angularity of the connecting rods, to secure the opening and closing of the inlet invention isto pro- 193s, serial No. 661,548

(c1. 12s-s3) and exhaust ports in a very suitable timed rela tion to each other, and .by the peculiar positioning of the combustion chamber, a very suitable degree of turbulence is obtained in the working charge at the moment of fuel injection.

The invention further consists in the combination and arrangement of parts set forth in the following specification taken in connection with the accompanying drawing. in which;

Fig. 1 is a vertical sectional view taken through -an internal combustion engine embodying the present invention.

Fig. 2 is a fragmentary sectional view taken substantially along the line 2-2 of Fig. 1.

Fig. 3 is an end elevational view; and

Fig. 4 is a fragmentary view shown partially in section and partially in elevation and taken along the line 4-4 of Fig. 3.

Referring now to the drawing and to Fig. 1 thereof, a portion of an internal combustion engine is shown, having a crank case I0 provided with motor supportqarms II and I2, a crankshaft I3, and connecting rods I4 and I5 which connect the crankshaft with pistons I6 and I1 adapted to reciprocate within parallel cylinders I8 and I9 positioned in a cylinder block suitably mounted upon the crank case.

In order to effect a compact arrangement of parts resulting in an engine of relatively small over-all dimensions, the cylinders I8 and I9 of each pair, as shown, extend vertically and are positioned above and upon opposite sides of the center line of the crankshaft and at right angles thereto, but are arranged in closely adjacent relation to each other. This arrangement also aids in providing a construction wherein the intake and exhaust ports are opened and closed in suitable timed relation, as will later appear.

Each ofv the cylinders is provided with a row of ports, 2| and 22 respectively, around the peripheral walls thereof, the ports 22 in the walls of the cylinder I9 acting, in this case, as air inlet ports and the ports 2 I in the cylinder I8 providing Imeans for exhausting the gases of combustion. An intake manifold 23 is suitably secured to one side of the cylinder block in open communicationwith the cylinder I9 through the intake ports 22, and an exhaust manifold 24 is likewise positioned on the opposite side of the cylinder block In open communication with the cylinder Il through the ports 2l. As is well understood in the art, fresh air is drawn or forced into the intake manifold 23, in a manner to later appear, and enters the cylinders, which are in open communication with Veach other,

through the intake ports 22, and the exhaust gases, after combustion takes place, are conveyed through the ports 2| of cylinder I 8 to the exhaust manifold which carries them away from the en- 5 gine.

A common cylinder head 25 is suitably secured in the. usual manner to the top of the cylinder block, thus covering the upper ends of the cylinders, and a fuel injection nozzle 26 of well known construction is removably secured in the top of the cylinder head, in communicating relation at its inner end with a combustion chamber 21 formed in the cylinder head The injection nozzle 26 may be formed in-the well known manner to ll5v inject a substantially conically formed fuel spray into the combustion chamber. i

The combustion chamber 21 is common to both cylinders of a pair and may be substantially coni- 'cal Ain form and of the proper size to conform in shape to the entering fuel spray injected by the nozzle 26. As shown by the dotted lines E in Fig. 2, the combustion chamber ispositioned in the cylinder head at a'point to lie substantially midway between the cylinders in open communication with each, the vertical axis thereof being offset from each of the cylinder axes. It will be seen that by this construction the chamber 21 performs a double purpose in that it provides a communicating air passage between the cylinders as 30 well as a combustion space therefor. Moreover, due to the peculiar -shape and. positioning of this chamber between the cylinders and in axial offset relation to each, a very desirable amount of turbulence is produced in the working charge at the time the fuel injection takes place.

As shown in Fig. 2 the cylinders are slightly offset 'from each other along the axis of the crankshaft. This construction serves a three-fold purpose, in that it, together with the combustion 40 chamber 21, effects the desired turbulence referred to above, and makes 'possible a construction which is very compact in form and having relatively small overall dimensions. Moreover, by arranging the cylinders in axial offset relation and on opposite sides of the crankshaft, as above de- -s'cribed,- it is possible to employ, identical. connecting rods which may be secured to a common crank pin.

As shown in Fig. 4, the connecting rods Il and I5 are identical in form and are rotatably secured by their crankshaft ends to a common crank pinv 3| in any suitable well known manner. By employing separate connecting rods, the cylinders will have less right'angleoil'set relative to the crankshaft than would be possible by the use of a single connecting rod having branches extending to each piston, and due to the resultant varyying angularity of the connecting rods,- a suitable timing for the opening and closing ,of the intake and exhaust ports may be secured. f' With'the present type of engine it is desirable that/ an air compressor be employed in connection therewith, in lorder to supply a sumcient amount of air to support proper combustion at highspeeds. In Figs.,3 and 4 a compressor or blower 22 of the Root" type is shown, which may 31 also mounted in bearings 42 in the blower casblower is mounted. A third gear 38 may be suitably mounted upon the blowerv casing and connected to drive any other engine auxiliaries (not 5 shown).

As shown in Figs. 2 and 3, the compressor rotors move in the direction of the arrows, forcing the air into a conduit 39 which connects the rotor chamber with the intake cylinder I9 through air 10 passages, formed in the cylinder block, and the intake manifold 23, as shown by the arrows in Fig. 2. y V

As is well known. fuelis injected through the nozzle 26, in the form of a conical spray, into the 15 combustion chamber 21 as each piston nears the `top ofits stroke. When each of the pistons reaches the top of its stroke, combustion takes place within the chamber 21, due to the high temperaturevvof the compressed air, thus forcing the 20 piston downwardly within its cylinder. 1

As indicated in Fig. l, when the center line `of the crank pin crosses a point on the line A the exhaust ports will be uncovered by the piston I6. When the crank pin crosses a point on the line B, 25 the intake ports' will be uncovered by the piston I1 and when itcrosses a point on line C the exhaust ports will be closed. Likewise, when it crosses a point on the line D the intake ports will be desea i It will thus be seen that the exhaust 30 l ports are opened an appreciable amount of time ahead of the inlet ports and are closed ahead -rather than after the inlet ports.

It will further be seen that, due to the offsetting of the cylinders along the axis of the crankshaft, 35 it is possible to make use of identical connecting rods secured to acommon crank pin. Such utilization of duplicate parts results in a very small tlrst cost of the engine, and by such construc-` tion,v an engine of relatively small over-all di- 40 mensions is provided.

It will be 'apparent that by the present i vention, a novel arrangement of cylinders, connecting rods, and combustion chambers is provided, with tlie result that an engine which is 45 simple in construction, eflcient in operationeco nomical to manufacture, and most compact in form, is the result.

Whileonly one specific embodiment has been shown and described, it will be apparent to those 50 skilled in the art that the invention is 'susceptible of numerous changes in construction and design without departing from the spirit or scope thereof, which is to be limited. only .by the appended claims. 55

, What I claim and desire to secure by Letters Patent is:

1. In an internal combustion engine having a crankshaft, a pair of parallel-adjacent cylinders arranged in spaced relation along the axis of the .o0 crank shaft, said `cylinders lying entirely l10n opposite sides of the center line of the crankshaft, and. a cylinder heed having a conically formed combined combustion chamber and air e positioned between the cylinders in open 65 communication with each and in axial offset relation thereto providing turbulence of the 'air in shaft provided with a crankpin. a pair'of par- 70 allel cylinders arranged side by side with one entirelyoneach'sideof saidcrankshaftand oil'- set from each other bothsalong theaxis of the crankshaft and in a direction at right angles thereto, e cylinder-heed having e combustion 74s.A

chamber formed therein in communicating relation with each of said cylinders whereby the combustion chamber also serves as a communicating air passage between the cylinders, a nozzle adapted to spray fuel into the combustion chamber, said fuel nozzle and combustion chamber lying between the axes of the two cylinders whereby a turbulence of the working charge is provided at the time fuel is injected, inlet and exhaust ports arranged respectively in the walls of each cylinder, a piston in each of. said cylinders, a separate connecting rod for each of said pistonsrotatably secured to said crank pin whereby the exhaust ports in one cylinder may be uncovered by the associated piston in advance of the uncovering of the inlet ports in the other cylinder and may be closed ahead of said inlet ports, an air compressor associated with the engine for providing airy to clean and ll the cylinders, and connecting means between said air compressor and the inlet ports.

3. In a fuel injection engine, a crankshaft, a pair of cylinders arranged entirely one on each side of the center line of said crankshaft and oilset both at right angles to and along the axis thereof, a cylinder head having a c'onically formed combustion chamber therein extending over only a relatively small portion of an end of each of said cylinders, and a fuel injection nozzle in com Inunication with said combustion chamber.

4. In a fuel injection engine-.providedwith a.

crank-shaft having crank pins, a pair of cylinders positioned one entirely on each side of the s centerline of said crankshaftand offset at right angles to and along the axis thereof, pistons in said cylinders, duplicate connecting rods between said pistons and said crankshaft, said connecting rods being rotatably secured to the same crank pin, a cylinder head having a combustion chamber formed therein of such size and shape as to extend over only a relatively small portion of an end of each of said cylinders, and a'fuel injection nozzle in communication with said combustion chamber.

5. In a fuel injection engine having a crankshaft. a pair of parallel cylinders arranged one entirely on each side of. the centerline of said crankshaft and offset both at right angles to and along the axis thereof, and a cylinder head having a conically formed combustion chamber therein, the axis of said chamber lying between said cylinders and the base portion thereof being of such diameter as to overlap but a relatively small portion of the top of eachk cylinder thereby serving as the communicating air passage between said cylinders and providing turbulence of the air charge at the time fuel is injected.

6. In an internal combustion engine having a crank shaft provided withl crank pins, a, pair of cylinders arranged one on each side of the center line of said crank shaft and onset from each other along the axis thereof, a piston in each of. said cylinders, and a pair of identical connecting rods connected at one end to said pistons and at the other end to a common crank pin of said crank shaft, said connecting rods being angularly bent from a point on the bodies thereof to the crank shaft ends thereof.

7. In an internal combustion engine having a crank shaft provided with crank pins, a pair of cylinders arranged one on each-side of the center line of said crank shaft and offset from each other along the axis thereof, a piston i'n each of said cylinders, and apair of angularly bent connecting rods connected at one end to said pistons and at the other end to a common crank pin of. said crank shaft, said connecting rods being positioned so that the angular portions thereof extend oppositely from said crank shaft respectively toward planes extending through the axes of said pistons.

8. In an internal combustion engine having a crank shaft provided `:vith crank pins, a pair of parallel cylinders arranged one on each side of the center line of said crank shaft and offset from each other along the axis thereof, a piston in each of said cylinders, a pair of identical connecting rods connecting said pistons to a crank pin of said crank shaft, each of said connecting rods being formed -to provide a portion extending along a plane through the axis. of. one of said pistons and a portion extending angularly from said plane to said crank shaft.

9. In an internal combustion engine having a crank shaft provided with crank pins, a pair of parallel cylinders arranged one entirely onl each side of the center line of said crank shaft and offset from each other both at right angles to and along the axis thereof, a piston in each of said cylinders, a pair of identical connecting rods connecting said pistons to a common crank pin of said crank shaft, each of said connecting rods being angularly bent to extend from a plane along the axis of said crank shaft toward a plane through the axis of. one of said pistons.

10. In a fuel injection engine having a pair of adjacent cylinders, a cylinder head having a conically formed combined combustion chamber and communicating air passage positioned between the cylinders in open communication therewith, the axis of said chamber lying between said cylinders in axial offset relation thereto and the base portion of said chamber being of such diameter as to overlap only a relatively small portion of the top of each cylinder thereby providing high turbulence of the air charge at the time fuel is injected. A

C M. BLANCHARD. 

